Headphone Amplifier question

trejo.

trejo.

trejo.

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I'm wondering if someone in to their audio could offer me some help!

I've always only ever used on board audio and I'm a little confused....

I was looking at this sound card https://www.overclockers.co.uk/showproduct.php?prodid=SC-015-AS&groupid=701&catid=11

But then I saw this https://www.overclockers.co.uk/showproduct.php?prodid=BU-256-OK&groupid=701&catid=11

If the cheaper card has a built in amp, what's the purpose of having the external amp?

I'm looking at getting a pair of Sennheiser HD598 Headphones for gaming predominantly but I will also use them for listening to music & films so need an all rounder.

Though I'm stuck at what card to get

There are even these https://www.overclockers.co.uk/showproduct.php?prodid=SC-090-CL&groupid=701&catid=11 but as it says gaming am I better off steering away from a card like that if i'm looking for arr round audio quality?
 
The purpose of the Symphonia sound card and amp bundle, is that the O2 amp is of much better quality than the one found in the DGX. It's also more powerful, so will drive more demanding headphones with ease, whereas the DGX amp will struggle. DGX amp will be fine for easier to drive headphones and will provide a good volume boost above any sound card that does not have a headphone amp.

The SoundBlaster Z has a more powerful headphone amp than the DGX, but it's still not a patch on the O2. You'd only really need to consider the O2 amp for headphones that demand that bit more power, AKG K702 for example. HD598 are easy to drive, so you can use them from fine any sound card.

Only slight issue with the SB Z is that it has no gain setting. The gain setting increases the juice the headphones receive, if you like. Easy to drive headphone don't need the extra juice, so having the ability to select a lower gain setting is preferable, otherwise you get very high volume with only a few % on the volume control, which is the case with using easy to drive headphones with the SB Z. The Xonar cards that have headphone amps have gain settings.

I suppose it depends how loud you like the volume. Some people who don't like the volume too loud have found even 20% of the SB Z volume is too loud. Some guy even found 6% was too loud with his Audio Technica M50X headphones.

That slight issue aside, the SB Z is a better card than the DGX.
 
Marsman said:
The purpose of the Symphonia sound card and amp bundle, is that the O2 amp is of much better quality than the one found in the DGX. It's also more powerful, so will drive more demanding headphones with ease, whereas the DGX amp will struggle. DGX amp will be fine for easier to drive headphones and will provide a good volume boost above any sound card that does not have a headphone amp.

The SoundBlaster Z has a more powerful headphone amp than the DGX, but it's still not a patch on the O2. You'd only really need to consider the O2 amp for headphones that demand that bit more power, AKG K702 for example. HD598 are easy to drive, so you can use them from fine any sound card.

Only slight issue with the SB Z is that it has no gain setting. The gain setting increases the juice the headphones receive, if you like. Easy to drive headphone don't need the extra juice, so having the ability to select a lower gain setting is preferable, otherwise you get very high volume with only a few % on the volume control, which is the case with using easy to drive headphones with the SB Z. The Xonar cards that have headphone amps have gain settings.

I suppose it depends how loud you like the volume. Some people who don't like the volume too loud have found even 20% of the SB Z volume is too loud. Some guy even found 6% was too loud with his Audio Technica M50X headphones.

That slight issue aside, the SB Z is a better card than the DGX.
Click to expand...

Thanks for this info, how do the USB soundcards such as the Asus Xonar U7 compare out of interest?

it sounds to me that i'd be better off with a card with gain settings as I do tend to find that my volume is too loud. Though I am currently using a Steelseries Siberia V2 headset which is mediocre at best I know.
 
I'd say the U7 is at least as good as the Sound Blaster Z and a step up from the Asus DG and DGX. It has selectable gain control (low and high) from within the driver, a very decent DAC, excellent DSP for all your surround sound effects, a decent if not particularly powerful headphone amp and a volume control right there on your desk. While I don't think the amp is very powerful (neither is the SBZ), it is easily able to drive the Senn HD598s and if you did have a need of driving heavier loads in the future, such as the Senn HD 600/650 or AKG K702, then you would need to look at the Asus Xonar STX or a powerful external solution anyway.
 
Anything containing a speaker requires driving, even IEMs, it's just a question of how much power is required to allow them to perform optimally. In the case of the relatively efficient, 50 ohm (input impedance) Sennheiser HD 598, that isn't very much.
 
Does anyone have the SB ZxR?

https://www.overclockers.co.uk/showproduct.php?prodid=SC-091-CL&groupid=701&catid=11

I'm able to get hold of one for a reasonable price, it appears to have some further control & RCA in which is a bonus for my speakers.

Now i'm beginning to understand the purpose of sound cards a little better from what i'm reading here. I'm happy to pay for something which will provide me a good all round audio quality with also some scope for the future if I were to upgrade to a better set of headphones.

Plus i get my half year bonus this month so I have some money to spend.
 
Between 25Hz and 250Hz the input impedance of the HD598 rises from 50ohms (nominal) to almost 300ohms and back again. This means that without a very low impedance amplifier the bass will be boomy, imprecise and muffled due to the poor control of the voice coils at low frequencies. The term used in these circumstances is "damping factor" and is the input impedance of the headphones divided by the output impedance of the amp. The recommended value of this ratio is 8, so looking at several sound cards:

ZxR (38 ohms) d/f = 1.3
Sound Blaster Z (22ohms) d/f = 2.3
Asus Xonar U7 (20ohms) d/f = 2.5
Asus Xonar STX (10 ohms) d/f = 5

None are ideal for the HD598, which is a problem if you want to use surround sound through the headphones. If you only need stereo however, you could get something like the FiiO E10K (£60) which has an output impedance of just 1 ohm, giving a damping factor of around 50. While you would lose surround sound the sound quality would see a noticeable improvement.

Another option would be to look at different headphones because the majority are not anywhere near as susceptible to impedance mismatches as the HD series from Sennheiser. If you did choose this path, then you need to ensure that the amp is capable of driving the headphones, which is not just a matter of impedance but also sensitivity.
 
So what we're saying is there is no suitable amp to run the HD 598's? Damn this is confusing. I'd of expected Sennheiser to explain that it rises from 50ohm to 300ohm, that's pretty bad of them not to do that.
 
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It's the sound card manufacturers that are mostly to blame for having such high output impedances right across the board, it's sad when the lowest of all is 10 ohms. External DAC/Amps seem to have no trouble achieving output impedances of less than 1 ohm so it's obviously no big deal to implement.
 
rids57 said:
It's the sound card manufacturers that are mostly to blame for having such high output impedances right across the board, it's sad when the lowest of all is 10 ohms. External DAC/Amps seem to have no trouble achieving output impedances of less than 1 ohm so it's obviously no big deal to implement.
Click to expand...

So if this is 0.5 Ohm impedance this would be ideal? But I ought to couple this is a reasonably good sound card or is that not much of an issue when using an external amp? https://www.overclockers.co.uk/showproduct.php?prodid=SC-002-EA&groupid=702&catid=2852&subcat=2856
 
The O2 is decent for driving a broad range of headphones, though availability seems to be an issue at the moment of the Epiphany Acoustics version.
 
Connecting a headphone amp to a sound card is a minefield too. If you connect to the line out of the sound card you don't get the headphone surround processing and if you connect to the headphone out socket you'll be double amping, which degrades the sound quality.

If you can do without headphone surround processing then you could just use the FiiO E10K (£60), the Schiit Fulla (£75), the DacMagic XS (£100), Audioengine D3 (£100), Audioquest Dragonfly (£108) or any number of combined DAC/Amps, no need for a sound card.

If you really need the headphone surround processing then you'll get the best match with the Asus Xonar Essence STX but that's double the price of the U7.
 
Right ok, i'm really only going to notice the surround processing on games & movies though right?

I might go ahead and actually get both the Asus Xonar Essence STX and the FiiO E10K as I could actually have a purpose for the FiiO E10K anyway.

Are there any headphones you'd recommend over the HD598's? The AKG ones seem highly rated and slightly cheaper?

Reading some reviews online of the 598's it does sound like they leave much to be desired and i'm only really seeing good reviews from say PC mags etc rather than when you go on to an audiophile forum and they really start to pick the headphones to bits, this is where i'm seeing a lack from them for the money.
 
There's a B Grade STX for £80 which would be a fantastic match for the AKG K612 or AKG K702. With the K702, you can do a very easy mod (just removing two sticky pads inside the cups) which adds a lot to the bass without messing up the sound of everything else. I've done the mod on mine and never looked back. :D
 
Sennheiser HD598 there are much better options than these.
i wouldn't go near any sennheisers below the HD600's apart from thje sennheiser over ear momentums which are more for on the move usage.
Akg k701 all day long over the Hd598.
 
Momentums are pretty nice to be fair - though they are designed at on the move use - very easy to drive, good clear mid-range, reasonable treble and a fairly satisfying if a bit gimmicky bass. Soundstage, etc. is a bit intimate but with a "binaural" like surround effect to it. Downside is they are ridiculously sensitive.


EDIT: Probably wouldn't recommend them as a main pair of headphones though - can listen to my 600s, etc. all day but the momentums can be fatiguing after awhile.
 
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Yea i wasn't meaning to recommend them more to say those are the only great sennheisers in my view below the HD600 price range.
 
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